Date   

locked Re: Batteries starting to get weak - MMM - What to do -

Mark McGovern
 

Matt,

That is true and Firefly batteries are technically lead acid batteries.  They are just so unique and unlike "traditional" lead acid batteries that I put them in their own category.

--
Mark McGovern
SM #440 Cara
Deale, MD USA


locked Re: Batteries starting to get weak - MMM - What to do -

Matt Salatino
 

Fire Fly doesn’t care if stored at 50% SOC

~~~⛵️~~~Matt

On Sep 12, 2020, at 3:29 PM, Mark McGovern <mfmcgovern@...> wrote:

Arno,

No problem.  That article that I linked to by Compass Marine is by far the most comprehensive that I have found regarding using LiFePO4 batteries in a marine electrical system.  I have read it many, many times and every time I re-read it I learn something new.

If I was not intending to move aboard full time and do extensive off-grid cruising, I would not have made the switch to LiFePO4.  The Firefly batteries you mentioned would be my choice for "part time" cruising.  They appear to have many of the same benefits of LiFePO4 regarding charge acceptance rate and Partial State of Charge use without the relative complexity and cost of installing a LiFePO system.

When thinking about SOC keep in mind that part of the beauty of LiFePO4 batteries is that, unlike Lead Acid batteries, they really don't care what the SOC is within a really wide range. They seem to be as happy at ~30% SOC as they are at ~90%.  They really just dislike the extremes, so the main job of the BMS (at least how Victron designs their BMS) is to keep the batteries from getting over-charged (over voltage) and getting over-discharged (under voltage) by cutting off charging source(s) or load(s).  Otherwise, the BMS doesn't really intervene in normal daily use (outside of intra-battery cell balancing which is a separate topic to itself and disallowing charging at temperatures below 5 deg C).

To give you some idea of the "new thinking" required with these batteries compared to Lead Acid when I took delivery of my batteries it was going to be several weeks before I could install them.  New batteries are delivered at about a 50% SOC.  When I asked my dealer how long I could leave them "as is" and what I needed to do to maintain them he said I could leave them that way for many months and probably years, and that I didn't need to do anything other than store them at a reasonable temperature.  Can you imagine what would happen to your Lead Acid batteries if they were left at 50% SOC for months?


--
Mark McGovern
SM #440 Cara
Deale, MD USA


locked Re: Batteries starting to get weak - MMM - What to do -

Mark McGovern
 

Arno,

No problem.  That article that I linked to by Compass Marine is by far the most comprehensive that I have found regarding using LiFePO4 batteries in a marine electrical system.  I have read it many, many times and every time I re-read it I learn something new.

If I was not intending to move aboard full time and do extensive off-grid cruising, I would not have made the switch to LiFePO4.  The Firefly batteries you mentioned would be my choice for "part time" cruising.  They appear to have many of the same benefits of LiFePO4 regarding charge acceptance rate and Partial State of Charge use without the relative complexity and cost of installing a LiFePO system.

When thinking about SOC keep in mind that part of the beauty of LiFePO4 batteries is that, unlike Lead Acid batteries, they really don't care what the SOC is within a really wide range. They seem to be as happy at ~30% SOC as they are at ~90%.  They really just dislike the extremes, so the main job of the BMS (at least how Victron designs their BMS) is to keep the batteries from getting over-charged (over voltage) and getting over-discharged (under voltage) by cutting off charging source(s) or load(s).  Otherwise, the BMS doesn't really intervene in normal daily use (outside of intra-battery cell balancing which is a separate topic to itself and disallowing charging at temperatures below 5 deg C).

To give you some idea of the "new thinking" required with these batteries compared to Lead Acid when I took delivery of my batteries it was going to be several weeks before I could install them.  New batteries are delivered at about a 50% SOC.  When I asked my dealer how long I could leave them "as is" and what I needed to do to maintain them he said I could leave them that way for many months and probably years, and that I didn't need to do anything other than store them at a reasonable temperature.  Can you imagine what would happen to your Lead Acid batteries if they were left at 50% SOC for months?


--
Mark McGovern
SM #440 Cara
Deale, MD USA


locked Re: Batteries starting to get weak - MMM - What to do -

Arno Luijten
 

Mark, Scott,

Thanks for the links and additional information.  Very interesting and helpful.

My point with using voltage to determine SOC is that the whole system on a boat in “action” is not stable. Your fridges turn on and off all the time. There is a cloud in front of your solar panel, a windgust for your windgenerator, you run a sheet winch, etc etc. So the voltage varies quite a bit because of fluctuating current draw and we just determined the voltage curve on Lithium is quite flat. How is your BMS to determine the SOC? This is why you really need a coulomb counter and some way to make it control your charging sources. Mastervolt has this mastershunt thing and some other stuff to make that happen but it quickly becomes very complex and maybe too complex for a bue water boat. I don’t know.
Anyway, for my usecase I think (as Scott rightfully says) it is not worth the trouble. I’m first going to try Firefly carbon foam batteries and in a few years we will see what the next best is. For those who spend most of the time off-grid lithium is much more attractive.

Regards,

Arno
SV Luna,
A54-121


Re: Gearbox ratio

Mark Barter
 

Thanks Mark, by complete chance I managed to capture that plate on our gearbox in a video I made. Now that I know what I am looking at I have the answer to my question. For anyone who needs to know the ratios are A: 2.74      B: 2.72
--
Mark & Nicky Barter
S/V Nunky
SM 110


Re: Ankerwinde Amel euros

Elja Röllinghoff Balu SM 222
 

Hallo Valentin
Ja die Winde scheint es zu sein , ich würde aber immer eine nehmen mit einem Verholspil
( einer Rolle an der Seite ) das erleichtert manchmal die Arbeit mit der Mooring .
Bei uns war ein Loch zum Kettenkasten ca 40 mm dadurch fiel die Kette direkt in den Kasten .
Das einzige Problem der Kasten ist nicht sehr tief und dadurch läuft die Kette dan auf und verstopft das Loch , dann must du die Kette mit der Hand wegräumen. Das kannst du aber mit einem ball fixiertan der richtigen Stelle umgehen , dann fällt fie Kette auf den Ball 🏀 unf verteilt sich besser .
Achte bitte darauf unsere Euros war eine Euros 39 !
Ich weiss nicht ob die Masse auf dem Vordeck etwas anders sind ,


Wenn du noch etwas brauchst jederzeit gern
Grüße Elja
SM Balu

Von meinem iPhone gesendet


locked Re: Batteries starting to get weak - MMM - What to do -

Mark McGovern
 
Edited

Scott,

Thanks for taking the time to reply.  I have read your posts with great interest and they have definitely helped me in planning and implementing my own system which shares many of the same components that you chose (i.e. I have lots of blue Victron stuff in my SM!).  

To be clear, I'm not saying that what the owner of MV Tanglewood is doing is the "correct" way to do it.  It certainly is not what most LiFePO4 manufacturers recommend.  I was simply stating that there does appear to be an observable and actionable correlation between voltage and State of Charge (SOC) with LiFePO4 batteries.  I totally agree that there is not a lot of "resolution" in the middle of the curve but there is enough resolution at the tail ends of the curve to take action before damage is done on either end of the curve.

Regarding the data posted that is posted here: https://www.powerstream.com/lithium-phosphate-charge-voltage.htm  you can see from the description of the test above the data that the test was done using very small batteries (less than 2.5 Ah capacity) and was done at over a 1C discharge rate (2.5 Amp discharge on 2.2 to 2.4 Ah batteries).  That is an extremely high discharge rate that is not really indicative of how we generally use our battery banks on our boats.  My normal "sitting at anchor" discharge rate is closer to 0.01C and I can even run one of the Air Conditioner units on the boat and still stay under 0.1C.  I think this high discharge rate has a significant impact on the Voltage vs. SOC results.

The data posted at the bottom of this article is from a test that I believe is much more indicative of how we use our battery banks:  https://marinehowto.com/lifepo4-batteries-on-boats/ and even this test is done at a relatively high discharge rate of about 0.075C.  Here is the chart of Voltage vs. Ah Discharged on the  772nd(!) Cycle on his ~11 year old LiFePO4 battery bank: https://marinehowto.com/wp-content/uploads/2015/09/34-LiFePO4-On-Boats.png


  


It's impossible to read the chart above but you can see the details in the links I that posted above.  I took the data from this 0.075C discharge test to get the following approximate Voltage vs. State of Charge %:

At 3.15v per cell or (3.15*4/8 = 12.6v/25.2v) you are at around ~15-18% SOC.
At 3.2v per cell or (3.2*4/8 = 12.8v/25.6v) you are at around ~30% SOC
At 3.3v per cell or (3.3*4/8 = 13.2v/26.4v) you are at around ~95% SOC
At 3.4v per cell or (3.4*4/8= 13.6v/27.2v) you are at around ~99-100% SOC

So on our nominal 24v boats there is a 1.2v difference from ~95%SOC to 15-18% SOC (26.4v-25.2v=1.2v).  That's not a huge difference, but it is easy to observe and use in decision making.

Other things to note in those test results:

  • He charges the bank to only 13.8v (3.45v per cell) with a 7.5amp tail current.  That's 27.6v on our 24v boat and is well below what most LiFePO4 battery manufacturers recommend. 
  • The battery bank reaches only 13.5v (3.37v per cell) at the start of the test with those charging parameters.
  • The voltage drops from 13.5v to 13.26v (3.32v per cell) after discharging only 6 Ah.
  • This data is from an eleven year old battery bank of LiFePO4 cells that has been in use in the lab and on a sailboat for and has had 773 cycles.  Most of those cycles have been to 80% depth of discharge or more.
  • This bank was rated at 400Ah when it was new but eleven years and almost 800 deep cycles later it still has MORE capacity than it was rated for when it was new.
Based on all of the above, Tanglewood's seemingly relatively simplistic scheme of charging to 3.45v per cell (but apparently only reaching 3.35v per cell or 26.8v on a 24v system), discharging normally, then charging again when the battery bank reaches 3.15v per cell (25.2v for Amels) seems pretty reasonable as it would cycle his batteries from 95% SOC to 15=18% SOC.  Only time will tell!  Hopefully he will continue to post his findings, good or bad. 

--
Mark McGovern
SM #440 Cara
Deale, MD USA


locked Re: Batteries starting to get weak - MMM - What to do -

Scott SV Tengah
 

Mark,

I looked at his first post and a few things he stated that is not consistent with the known characteristics of lithium:

1) Take a look at the voltage vs. SOC graph for a Lifepo4 battery. 
https://www.powerstream.com/lithium-phosphate-charge-voltage.htm

At 3.2v per cell or (3.2*8 = 25.8v) you are at around 3-8% state of charge.
At 3.3v per cell or (3.3*8 = 26.4v) you are at around 20-31% state of charge.
At 3.4v per cell or (3.4*8= 27.2v) you are at around 96-99% SOC. 

But it's not just the spread, it's the shape of the curve. The challenge is that the lithium curve, unlike lead, is NOT linear. The middle portion between say 10% and 90% has a very flat voltage curve.  See link above. I can attest that with my Mastervolt 110A charger set to 27.5v absorption, the alternator has stopped charging anywhere between 75-100%, averaging 85%.

If you set your charger to stop charging at 26.8v, you may be charging your batteries to only 40-50%.

And as you can see with lead, the voltage vs. SOC curve is quite linear, making it far more useful to determine SOC from voltage.
https://www.researchgate.net/profile/Jeff_Cherry2/publication/315847359/figure/fig2/AS:633864561106948@1528136496496/Typical-Open-Circuit-Voltage-OCV-of-12V-Lead-Acid-Battery.png

2) He stops charging at 3.45v per cell and has a high voltage alarm at 3.5v. His high voltage ALARM is below Victron's absorption voltage of 3.55v and below Mastervolt's absorption voltage of 3.6v. Keeping voltage low like that will help avoid high SOC induced imbalances but there are other sources of imbalance too, namely high load or imperfectly assembled batteries. And most cell balancing systems require you to charge to near full before they start balancing, as indicated by low charge current acceptance rate - namely because of the non-linear charge curve. I have had batteries that show perfect balance until you approach 3.5v+ and then one cell goes wildly out of balance.

By not charging your batteries fully every once in a while, you may end up prolonging a cell imbalance issue that, in the event that you need to draw the batteries quite deeply (big storm, can't run the genset because of sea state), could result in a cell LOW voltage problem that will destroy the battery or cause your BMS to disconnect your loads at the worst time. Further, most battery monitors determine state of charge based on calibrating to 100%. And 100% on my battery monitor is determined when charge current is below X for time period Y. That means the battery is full and no longer accepting charge. As such, Victron explicitly recommends charging fully once a month to recalibrate the SOC monitor.



--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com


locked Re: Batteries starting to get weak - MMM - What to do -

Mark McGovern
 

Arno,

Voltage may not be as bad an indicator of SOC of LiFePO4 batteries as you might think.  Here's a quote from the owner of MV Tanglewood who has had his LiFePO4 bank in operation for about ~18 months now:

First, counter to what everyone says, I think battery bank voltage is a sufficiently close indicator of SOG.  People say it's a much worse indicator for LFP vs Lead, but I disagree.  My lead bank was 50.4 volts when fully charged, and 48.0V when is was 50% empty and the generator started.  That's a spread of 2.4 volts.  In contrast, my LPF bank is full at 53.6V, and ready for recharge at 50.4V.  That's a 3.2V spread and is 30% more voltage swing than lead.  The difference, though, is that in the mid area of charge, the LFP voltage doesn't vary much, so there isn't as much differentiation between 60% and 50%.

Granted, this 3.2v spread is for his nominal 48v system but even with our nominal 24v system it would be a 1.6v spread which is a significant enough spread to monitor and act on.  I am literally in the middle of installing my LiFePO4 system and I am not yet living full time on the boat so I don't have a ton of personal experience with it just yet.  However, the experience that I do have so far lines up with Tanglewood's experience.  I think that if you operated an LiFePO4 system simplistically such that it is assumed to be "full" at 26.8V (stop charging) and then "empty" at 25.2v (start charging), the battery bank would be quite happy and would give you many years of service.

Here is the full blog post:  http://www.mvtanglewood.com/search/label/Lithium%20Batteries  

Be sure to read his other LiFePO4 related posts.  They are full of great information.
 
--
Mark McGovern
SM #440 Cara
Deale, MD USA


locked Re: Batteries starting to get weak - MMM - What to do -

Elja Röllinghoff Balu SM 222
 

He jose 
For the capcity you take Vicron the deal 12 v 200 ah for the normal sice 
Ore loog by green accu 
The you get 24 V 200 ah 
Best Elja 

Von meinem iPhone gesendet


locked Re: Batteries starting to get weak - MMM - What to do -

Scott SV Tengah
 

Arno,

I actually think if you're on shore power most of the time, lithium is a bad idea. At best, it's a waste of money that adds additional complication. 

I do agree with your lack of confidence in the warranty. Unless you are using batteries and chargers from one brand, I am almost certain the battery manufacturer will point fingers at the charger and you will left paying for a new battery bank yourself. 

For me, the big pluses are the charge/discharge curve as you mentioned, the lack of need to keep it full, the ability to run virtually all 220v appliances on battery and one thing that people don't often think about is that it could effectively double your solar output. The charge acceptance rate and near nonexistent charging efficiency issues means that, for the same solar array, you will get almost twice as many AH per day into your batteries compared to lead. I believe it is Porter who is in the tropics and has a similar solar array and the same MPPT as we do, but we are able to put nearly twice as much cumulative power into the batteries as he is. Our only difference is AGM vs. lithium.

--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com


locked Re: Batteries starting to get weak - MMM - What to do -

Scott SV Tengah
 

Sounds about right with Mastervolt. I haven't studied their system in detail but from what I've seen, they're the most hands off, from the user perspective, that I've seen. But you pay for it!

I have the Mastervolt alternator and Alpha pro II (3 is even better) and it took me over a year and the help of an engineer who used to break into car ECUs to reprogram them. It turned out to be quite simple, but neither Victron nor dealers understood the problem or could provide the solution.

I describe how I do it here:
https://amelyachtowners.groups.io/g/main/message/50689

One final alternator tip: I did not use the standard lithium profile on the mastervolt charge controller. This is because I did not want to keep the lithium batteries fully charged when motoring for a long time as this is not good for the batteries. I set the absorption voltage for 27.5v and the "float" at 26.5v. As mentioned before, voltage is NOT a good indicator of SOC, but I've seen over the last two years that this seems to result in charging stopping at around 85% on my system.  You'll need a Mastervolt USB interface to program your charge controller.

https://www.mastervolt.com/products/masterbus-interfaces/masterbus-usb-interface/


--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com


Re: Scuba compressor recommendations

Scott SV Tengah
 

I do something similar but it's just a Ryobi portable fan that I direct at the compressor when I'm filling tanks. Bauer techs told me that it will extend the life of the compressor and the filters. Your blower fan will certainly work better.

One other idea is to take a long hose and bring fresh air into the intake. This is something gasoline powered compressors have to do but we do it also because our cockpit locker also stores chemicals that I prefer not to breathe underwater (or above water, for that matter!).

--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com


locked Re: Batteries starting to get weak - MMM - What to do -

Jose Venegas
 

I was searching over internet for marine Lithium Batteries and found the “Ionic” brand that sells a 12V 125 Ah with the same size of the BattleBorn 12 100 Ah battery.
Ionic only give 5 years warranty vs BB 10 years, but they will provide 25% more capacity for our boats and each battery can be monitored independently with a smart phone via blue tooth communication.
I am inclined to go BB but wonder if any one has heard good or bad things of the “ionic”

Jose Venegas
IPANEMA SM2K 278
Curaçao


Outhaul gear pulled in Annapolis

Karen Smith
 

Hi!  Bill Kinney & I have been doing some work with new owners of an Amel 54. The outhaul is really stuck. Is there anyone in the group near Annapolis with a pulled for the outhaul that we could borrow? It would be greatly appreciated! If you are in the area we will be at Bert Jabins Yacht Yard please stop by and say hi!

Karen Smith
s/v Harmonie
SM #160


Re: Gearbox ratio

Mark McGovern
 

Mark,

My SM is a 2004 with a Yanmar 4JH3-HTE engine.  It does have a Hurth ZF25 gearbox.  However, it may not be the same gearbox on your SM with a Perkins M80T. 

In any case the ratios on my gearbox are as follows:

Ratio 1:  A = 2.80 B = 2.80

I'm not sure what you are going to use the ratio information for, but the only way to be 100% certain what is on your boat is to look at the plate that is on the gearbox in your engine room.   Maybe you can get someone to go on your boat and take a picture for you.  Here is the plate on my gearbox:



I find that Google Photos is a great way to store information like this "for posterity" so that you can find and access the information even when you are not on your boat.  That's what I just used to grab the photo above.  I took that pic over a year ago for no real particular reason but to document what I had while I was replacing the Vetus coupler.

--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: A54 hawsehole and chain guide

Teun BAAS
 

Morning Thomas,

 

Thanks for the reply – all clear.

 

Best Regards Teun

A54 2009 #128

September 11, 2020 08:56:48

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Sv Garulfo via groups.io
Sent: Wednesday, September 9, 2020 11:36
To: main@amelyachtowners.groups.io
Subject: Re: [AmelYachtOwners] A54 hawsehole and chain guide

 

Hi Teun,

 

No, it’s only when we let out the full chain for whatever reason. So it’s very rare and only to minimise the chance of bungling it during business as usual. (That rarely happens anyway, even with galvanised chain). 

 

Hope that clarifies the use case. 

 

 

Thomas 

GARULFO 

A54-122

Bora-Bora 

 

 

 

 

On Tue, 8 Sep 2020 at 03:48, Teun BAAS <teun@...> wrote:

Thomas,

 

Does this mean that every time you weigh anchor that somebody is guiding this device by hand in the right direction to evenly spread the anchor chain?

 

If so then I clearly have too many sails in the sail locker as it is completely full and was really a massive, massive head ache to get to the chain locker when the new (galvanized) chain bungled up. I never had the bungling up issue with the OEM SS chain and since I pushed a bunch of the galvanized chain all the way to the back it hasn’t happened since. It is rare, even in the South Pacific, that I use the last 30 meters of a 100 meter chain so pushing those 30 plus meters all the way back in the chain locker I believe prevents the bundle of chain getting too high in the front and thus getting tangled/bungled.

 

But your device looks what I need but then I also need: A) easily access to the chain locker as well as B) a pair of hands during departure.

 

Best Regards Teun

A 54 2009  #128

September 8, 2020 06:46:43

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of Sv Garulfo via groups.io
Sent: Sunday, September 6, 2020 15:07
To: Amel Yacht owners Group <main@amelyachtowners.groups.io>
Subject: [AmelYachtOwners] A54 hawsehole and chain guide

 

Hi all,

 

We recently end-to-ended our anchor chain and I found the pictured device useful to guide the chain nice and flat at the bottom of the chain locker.

 

It’s simply a piece of PVC pipe with a couple of small line to gutter the chain in various corners of the locker.

 

 

 

And when you don’t use it, it snaps happily on the hawsehole pipe for efficient storage. 

 

 

 

 

Best,

 

Thomas

GARULFO 

A54-122

Bora-Bora 

 


Re: Scuba compressor recommendations

Arlo
 

thanks for the details. Why did they put it on a track? 


Re: Scuba compressor recommendations

Arlo
 

thanks Scott! Great tip...I plan to install a blower fan as well on it to help keep it cool...


Re: Scuba compressor recommendations

Arlo
 

Thank you! all good to know. anything I should be aware of to check if I buy a used system?

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